This article is an attempt to show the role which is assumed by ethics when it is conceived as a work, or a thought that nourish itself in its field of application, which is in this case the field of psychology and psychiatry. After having described some of the major characteristics of the human being as a single and relational being, we will show the dynamics of violence. Not all of them are necessarily morally unacceptable, because some of them are favorable, even required for the development of human life. From an ethic point of view violence is acceptable when it encourages the inclusion of the third, that is usually excluded. The included third is the best method of ethics because it accepts the dynamic of the conflict instead of denying or hiding it behind false dualisms. Included third is also the fundamental premise of transdisciplinarity, namely the creative meeting of different disciplinary universes that cross themselves in a subject who always holds a dialogue with the same subject. The article ends with the analysis of a therapeutic practice, whose protagonists are the ethicist, the psychiatrist and their patient.
Keywords: Ineffability, mutual autonomy, violence (symbolical/diabolical), word, third, transdisciplinarity